Foundation pit protection device

The utility model relates to the technical field of foundation pits, and discloses a foundation pit protection device which comprises a base, a fixing groove is formed in the upper surface of the base, a left fixing block is fixedly connected to the other side face of the base, a left supporting groove is formed in the upper surface of the left fixing block, and a left supporting block is arranged in the left supporting groove. The other side face of the base is fixedly connected with a right fixing block. The utility model has the following advantages and effects: by arranging the base, the left support column and the right support column, a worker places the base at a fixed position during working, and then respectively installs the left support column and the right support column in the left support groove and the right support groove; and then the upper top plate is installed on the left connecting groove and the right connecting groove in the left supporting column and the right supporting column, and fi